# abranchialism

CEFR C2 · Noun

Source: https://englishreference.com/word/abranchialism
Updated: 2026-05-18

## Definition

a rare word for the state of not having gills. It describes animals that do not use gills to breathe underwater.

For teachers: the condition or state of being without gills. Refers to organisms that lack the specialized respiratory structures used for gas exchange in aquatic environments.

## Examples

- The study explores abranchialism in certain deep-sea species.
- Scientists are investigating abranchialism in these ancient fish to understand how they survived in oxygen-poor waters.
- The evolutionary transition from aquatic to terrestrial life often involves the loss of abranchialism, as lungs replace gills for oxygen extraction from the air.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.